1.Material:Low carbon steel 2.Top: plain 3.Cross bar: round 4.Standard:ANSI/NAAMM(MBG531 ... our TaskMaterial:carbon steel or stainless steel,aluminumBearing bar:from 20x3mm to 100x10mm/ I section from 25x5x3mm ... bar25x3,25x4,30x3,30x4,30x5,32x5,40x5,50x5,.....75x10mm2Bear bar pitch12.5, 15, 20, 23.85, 25, ... around in the world. Round cross bar concrete plain top mild steel grating